comparative circulatory system
DESCRIPTION
Two Different Circulatory Systems Open Circulatory System Blood (hemolymph) is pumped into open body cavity (hemocoel). Blood reenters heart through openings (ostia). Does not require much energy to operate, but can’t sustain high levels of activity. Closed Circulatory System Blood is contained within blood vessels: Arteries move blood away from the heart. Veins move blood toward the heart. Energetically costly to operate, but allows higher levels of activity.TRANSCRIPT
Comparative Circulatory System
The function of animal circulatory systems is mainly…
AND…
Transport of O2 to the cellsTransport of CO2 out of the body
Transport of nutrients
Two Different Circulatory Systems• Open Circulatory
System• Blood (hemolymph) is
pumped into open body cavity (hemocoel).
• Blood reenters heart through openings (ostia).
• Does not require much energy to operate, but can’t sustain high levels of activity.
• Closed Circulatory System
• Blood is contained within blood vessels:– Arteries move blood
away from the heart.– Veins move blood toward
the heart.• Energetically costly to
operate, but allows higher levels of activity.
Invertebrate Circulatory Systems
Most Invertebrates have an open circulatory system.
Fish Circulation• A fish heart
has two chambers, one atrium and one ventricle.
• “Single-loop circulation” results in lower blood pressure in the body capillaries
Heart pumps blood to the gills to be re-oxygenated (gill circulation) after which blood flows to rest of body and back to the heart in one circuit.
Amphibian and Reptile Circulation• Amphibian and Reptilian
heart is a “Double-loop circulatory system.”
• Advent of lungs resulted in two circulations:– Pulmonary circulation -
(Lungs)– Systematic circulation -
(Rest of body)• Maintains blood pressure in
body capillaries• Oxygen rich and oxygen
deficient blood mix in the ventricle.
Mammalian and Bird Circulation
• Mammals, birds, and crocodiles have four- chambered heart.– right and left atria– right and left ventricles
• The right and left ventricles are separated by a muscular wall called the septum
• This prevents oxygen rich and oxygen deficient blood from mixing
• Made up of two pumping systems/circuits.– Pulmonary circulation– Systemic circulation
Comparison of Vertebrate Hearts
• Functions:– Transports
gases, nutrients, hormones, and waste
– Regulate body temperature
– Fight infection• Major Organs:
– Heart– Blood vessels
The Human Circulatory System
Circulation through body– Heart pumps blood
• Pulmonary circulation (heart to lungs to heart)
• Systemic Circulation (heart to body to heart)
Circulation through heart• Vena Cava• Right atria• Right ventricle• Pulmonary artery• Lungs• Pulmonary vein• Left atria• Left ventricle• Aorta• Body
Unoxygenated blood enters the
atrium on the right side of the heart.
Unoxygenated blood comes in
from the top of the body through the
superior vena cava.
Unoxygenated blood comes in from the lower
body though the inferior vena cava.
While the unoxygenated blood is in the right atrium, the tricuspid
valve is closed to keep the blood from
flowing down to the
ventricle.
The atrium
contracts and the tricuspid
valve opens, forcing
the blood down into
the ventricle.
The tricuspid valve closes again so that blood cannot move back up into the atrium.
The ventricle contracts. This forces
the unoxygenated blood through the pulmonary valve and into the pulmonary
arteries.
The right pulmonary artery takes the
unoxygenated blood to the right lung.
The left pulmonary artery takes the
unoxygenated blood to the left lung.
THE PULMONARY ARTERIES ARE
THE ONLY ARTERIES THAT
CARRY UNOXYGENEATED
BLOOD.
Oxygenated blood from the
lungs enters the heart through the
left atrium.
The mitral valve is closed to keep the blood from going into the
ventricle.
Oxygenated blood from the right lung returns to the heart
through the right pulmonary vein.
Oxygenated blood from the left lung
returns to the heart through the left pulmonary vein.
THE PULMONARY VEINS ARE THE
ONLY VEINS THAT CARRY
OXYGENATED BLOOD.
The left atrium contracts. This forces
the oxygenated
blood through the mitral
valve into the left ventricle.
The mitral valve closes again. This keeps the
oxygenated blood from
moving back up into the
atrium.
Oxygenated blood is forced into the aorta to be carried to the rest of
the body.
Blood Vessels• Tissues
– connective– smooth
muscle– endothelium
(type of epithelial tissue)
• Arteries• Veins• Capillaries
Blood• Connective tissue• Fluid structure
(can flow to all parts of the body)
• Blood Cells– Red blood cells
• lack nuclei• transport oxygen
– White blood cells• contain nuclei• fight infection
– Platelets• plasma proteins and
cell fragments responsible for clotting
• Blood Plasma– 90% water– 10 %
• dissolved gases• salts• nutrients• enzymes• waste• plasma proteins
– transport fatty acids, hormones, vitamins
– fight infections– involved in blood
clotting